
pagy yes 
on the toxicity of pyrethrum (light oil) spray to house flies (Musca 
domestica L.) * * * In a typical test three groups of six cages each 
were treated at each pressure (25, 50, and 100 pounds) to study the re— 
producibility of results." His tabulated results show that "50 pounds 
prescure gives a greater per cent mortality than either 25 or 100 pounds. 
A study of all the results indicates that the maximum per cent mortality 
is obtained when 40 pounds pressure is used with this particular spray." 
Blowfly parasites and predators active.~-R. A. Roberts, Uvalde, 
Tex., reports that "Brachymeria fonscolombei Duf. has been very active 
during April, emergence has been completed from the overwintering ma-— 
terial, a second generation has been secured from individuals which 
emerged in March, and there is abundant evidence of their activity in 
status jars exposed throughout the month. * * * Alysia ridibunda Say 
has completed its emergence from hibernation, and numerous fly larvae 
of several species and ages were exposed to the parasites, * * * Among 
the pupal parasites, there was an abundance of Mormoniella yvitripennis 
W1k. and some activity of Tricophria hirticollis Ashm., a species which 
with Xyalosema seems to be increasing from year to year in this area. 
Among the predators the greatest activity and abundance are among the 
various species of the genus Saprinus of the family Histeridae. As these 
beetles were active throughout the entire winter, they have bred up in 
large numbers and are very active around all carcasses." 

Control of sand flies and mosquitoes through drainage systems .—— 
"The handwriting on the wall seems to be that the control of sand flies 
can be interlinked with the control of salt-marsh mosquitoes through 
drainage systems," states W. E. Dove, Charleston, Sw Gepewho, wi ths die 
assistants is experimenting with creosoted pine sap spray on marshes. 
"For strictly mosquito control it is necessary to provide for an annu- 
al maintenance of the ditches. A cleaning out of the ditches could be 
done effectively when the sand-fly larvae could be treated. An objec- 
tion to this is the fact that the treatment of the ditches kills min- 
nows. It is our observation that following the treatment the minnows 
are quickly replaced. Until they are replaced by migration, the sump- 
age keeps the mosquito larvae under control. It is only a question of 
a day or two before an abundant supply of minnows comes in again." 
STORED PRODUCT INSECTS 
Paradichlorobenzene effective against the webbing clothes moth. -~ 
Tests completed in April by Wallace Colman, Silver Spring, Md., "show 
that continuous fumigation with low concentrations of paradichloroben- 
zone vapor gives complete protection to clothing from injury by larvae 
of the clothes moth .(Tineola biselliella Hummel). The success of such 
fumigation depends upon the fact that a chronic toxic effect, eviden- 
ced by a stoppage of all feeding, is produced by a concentration of the 
